Nicolaus Adriani (15 September 1865, Oud-Loosdrecht – 5 August 1926, Poso, Central Sulawesi) was a Christian missionary from the Netherlands who did work in Indonesia. He studied linguistics of the East Indies at Leiden University, obtaining his PhD in 1893. He was sent by the . He worked as a linguist in Poso, Central Sulawesi. In 1897 Adriani became correspondent of the Royal Netherlands Academy of Arts and Sciences, in 1918 he joined as member.